Drive arrangement

Abstract

A drive arrangement with a first motor and a second motor is described, the first and second motor being coupled via a first coupling unit. The first motor is provided to generate uniform low-frequency movements and the second motor performs a higher frequency alternating movement to be overlapped. The total movement is transmitted from the second motor to a machine component coupled via a second coupling unit. The first coupling unit is configured to transfer the uniform low-frequency movement of the first motor to the second motor, wherein a transmission of the higher frequency alternating movement of the second motor to the first motor is suppressed.

The invention claimed is: 
     
       1. A drive arrangement, comprising:
 a machine component; 
 a first motor with a constant torque for generating a uniform movement of the machine component; 
 a second motor with a dynamic torque for generating an alternating movement of the machine component; 
 a first coupling unit for coupling the first motor to the second motor, 
 wherein the first coupling unit transfers the uniform movement of the first motor to the second motor, and 
 wherein the first coupling unit suppresses a transmission of the alternating movement of the second motor to the first motor; and 
 a second coupling unit for coupling the machine component to the second motor. 
 
     
     
       2. The drive arrangement as claimed in  claim 1 , wherein the first coupling unit is a toothed belt. 
     
     
       3. The drive arrangement as claimed in  claim 1 , wherein the alternating movement comprises a periodic movement pattern with a constant basic frequency. 
     
     
       4. The drive arrangement as claimed in  claim 3 , wherein the first coupling unit is a soft coupling between the first motor and the second motor, and wherein the second coupling unit is a rigid coupling between the second motor and the machine component. 
     
     
       5. The drive arrangement as claimed in  claim 4 , wherein a resonant frequency of a system comprising the first motor, the second motor, the first coupling unit, the second coupling unit and the machine component are tuned to the basic frequency of the periodic movement pattern. 
     
     
       6. The drive arrangement as claimed in  claim 5 , wherein the resonant frequency is tuned by the first coupling unit. 
     
     
       7. The drive arrangement as claimed in  claim 6 , wherein the first coupling unit includes a coupling of a rotor of the first motor to a rotor of the second motor. 
     
     
       8. The drive arrangement as claimed in  claim 7 , further comprising:
 a closed-loop drive control of the second motor, wherein the closed-loop drive control is the coupling of the rotor of the first motor to the rotor of the second motor. 
 
     
     
       9. The drive arrangement as claimed in  claim 1 , wherein the drive arrangement is an extrusion machine, the first motor is a asynchronous machine and the second motor is a synchronous machine.